Tanks are conventionally metal or plastic material casks, in vertical or upright position. The emptying of said tanks requires the removal of drained solid matters after they have been separated from liquid juices.
In order to remove drained solid matters from the tank, an opening is provided at the base of the tank so that a suitable tool can be introduced in order to gather deposits and remove them.
It was also proposed in the previous art to provide a blade at the base of the tank, the diameter of which would be sustantially the same as the tank diameter, said blade being rotated by an electric motor attached to the bottom of the tank.
After emptying the liquid juice, the blade is rotated at low speed in order to bring together all solid deposits and to force them through an opening at the base of the tank.
The profile section of blades is selected so that deposits are concentrated on a sweeping ring close to the opening provided for removal.
However it is difficult to achieve a satisfactory tightness of the driving shaft. Moreover this type of equipment installed on tanks represents high investment and maintenance charges when the user has several tanks.